Whether you're doing household repair or automotive work， a Craftsman CM hex key ST BL end set is a fundamental addition to your tool collection. With rugged alloyed steel construction and precision machining， these hex keys fit tightly into sockets to prevent stripping and rounding over time. Covering the range of the most common metric sizes for hex sockets， this set delivers all you'll need to get the job done. Pair the sturdy steel alloy construction with Craftsman's Forever Guarantee and it's clear that this CM hex key ST BL end set is the last you will need to buy. A plastic carrying case securely holds and clearly identifies each wrench so you never have to fumble for the one you want. Grab these tough tools and get to work.